Submission #264805

# Submission time Handle Problem Language Result Execution time Memory
264805 2020-08-14T09:59:53 Z anubhavdhar Building Bridges (CEOI17_building) C++14
0 / 100
126 ms 2936 KB
#include<bits/stdc++.h>

#define ll long long
#define pb push_back
#define mp make_pair
#define pii pair<int, int>
#define pll pair<ll, ll>
#define ff first 
#define ss second
#define vi vector<int>
#define vl vector<ll>
#define vii vector<pii>
#define vll vector<pll>
#define FOR(i,N) for(i=0;i<(N);++i)
#define FORe(i,N) for(i=1;i<=(N);++i)
#define FORr(i,a,b) for(i=(a);i<(b);++i)
#define FORrev(i,N) for(i=(N);i>=0;--i)
#define F0R(i,N) for(int i=0;i<(N);++i)
#define F0Re(i,N) for(int i=1;i<=(N);++i)
#define F0Rr(i,a,b) for(ll i=(a);i<(b);++i)
#define F0Rrev(i,N) for(int i=(N);i>=0;--i)
#define all(v) (v).begin(),(v).end()
#define dbgLine cerr<<" LINE : "<<__LINE__<<"\n"
#define ldd long double

using namespace std;

const int Alp = 26;
const int __PRECISION = 9;
const int inf = 1e9 + 8;

const ldd PI = acos(-1);
const ldd EPS = 1e-7;

const ll MOD = 1e9 + 7;
const ll MAXN = 1e5 + 5;
const ll ROOTN = 320;
const ll LOGN = 18;
const ll INF = 1e18 + 1022;

int N;
ll dp[MAXN], pre[MAXN], h[MAXN];

struct line //mx + c
{
	mutable ll m, c, p;
	bool operator < (const line& o) const {return m < o.m;}
	bool operator < (ll x) const {return p < x;}
};

struct CHT_black_box : multiset<line, less<>>
{
	int mode;
	void set_mode(string S) {mode = (S[1] == 'i' || S[1] == 'I') ? -1 : 1;}
	ll div(ll a, ll b) {return a/b - ((a^b) < 0 && a%b);}
	bool isect(iterator x, iterator y)
	{
		if(y == end()){x->p = INF; return false;}
		if(x->m == y->m)	x->p = (x->c > y->c) ? INF : -INF;
		else	x->p = div((y->c - x->c),(x->m - y->m));
		return (x->p >= y->p);
	}
	void add(ll slope, ll intercept)
	{
		auto z = insert({mode * slope, mode * intercept, 0}), y = z++, x = y;
		while(isect(y, z))	z = erase(z);
		if(x != begin() && isect(--x, y))	isect(x, y = erase(y));
		while((y=x) != begin() && (--x)->p >= y->p)	isect(x, erase(y));
	}
	ll query(ll x)
	{
		assert(!empty());
		auto l = *lower_bound(x);
		return mode * (l.m * x + l.c);
	}
}box;

signed main()
{

	/*
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);
	*/

	ll w;
	cin>>N;
	F0R(i, N)
		cin>>h[i];
	F0R(i, N)
		cin>>w, pre[i] = w + ((i == 0) ? 0 : pre[i-1]);

	box.set_mode("min");

	dp[0] = 0;
	box.add( - 2*h[0], h[0]*h[0] + dp[0] - pre[0]);

	F0Re(i, N-1)
	{
		dp[i] = (h[i] * h[i] + pre[i-1]) - box.query(h[i]);
		box.add(- 2*h[i], h[i]*h[i] + dp[i] - pre[i]);
	}
	
	//F0R(i, N)
	//	cout<<"dp["<<i<<"] = "<<dp[i]<<'\n';
	cout<<dp[N-1]<<'\n';

	return 0;
}
# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 384 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 126 ms 2936 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 384 KB Output isn't correct
2 Halted 0 ms 0 KB -